Researchers led by a team at UT Southwestern Medical Center have developed a device that can isolate blood flow to the brain, keeping the organ alive and functioning independent from the rest of the body for several hours.
The device, tested using a pig brain model and described in Scientific Reports, could lead to new ways to study the human brain without influence from other bodily functions. It also could inform the design of machines for cardiopulmonary bypass that better replicate natural blood flow to the brain. The findings build on previous research by study leader Juan Pascual, M.D., Ph.D., and his colleagues.
“This novel method enables research that focuses on the brain independent of the body, allowing us to answer physiological questions in a way that has never been done,” said Dr. Pascual, Professor of Neurology, Pediatrics, and Physiology, and in the Eugene McDermott Center for Human Growth and Development at UT Southwestern. Dr. Pascual is a member of the Peter O’Donnell Jr. Brain Institute at UTSW.
The brain is the body’s master controller for a variety of processes, regulating heart rate, breathing, and sleep and wake cycles, among others. In turn, the brain’s function is affected by factors that originate in the body, such as blood sugar, blood pressure, and oxygenation. Until now, Dr. Pascual explained, there has been no way to separate the brain from the body to study these influences.
In an animal model using anesthesia, the researchers redirected the brain’s blood supply through a pump that maintained or adjusted a range of variables, including blood pressure, volume, temperature, oxygenation, and nutrients. The team found that brain activity and other measurements had minimal to no changes over a five-hour period.
Isolating the brain will allow researchers to manipulate inputs to this organ to study how they change brain function without the body’s influence. For example, Dr. Pascual said, he and his colleagues have already used this system to better understand the effects of hypoglycemia (low blood sugar) in the absence of other factors. Although scientists can induce hypoglycemia by restricting food intake in lab animals or dosing them with insulin, the body can partially compensate for either of these scenarios by altering metabolism and this, in turn, alters the brain. In contrast, the new device allows researchers to alter the glucose content directly in blood pumped to the brain.
Cardiopulmonary bypass devices replicate some functions of the heart and lungs, delivering a continuous flow of oxygenated blood throughout the body. In contrast, the new device delivers blood using a pulsative flow, much like the human heart, a difference that may prevent brain-related side effects sometimes caused by cardiopulmonary bypass machines. Dr. Pascual said this device has been patented to test its effectiveness for this indication.
Dr. Pascual holds the Ed and Sue Rose Distinguished Professorship in Neurology and The Once Upon a Time Foundation Professorship in Pediatric Neurologic Diseases.
Other UTSW researchers who contributed to this study include co-first authors Muhammed Shariff, Visiting Junior Researcher in Neurology, and Aksharkumar Dobariya, M.S., Graduate Student Researcher in Biomedical Engineering; Bret Evers, M.D., Ph.D., Assistant Professor of Pathology and Ophthalmology; Ulrike Hoffmann, M.D., Ph.D., Assistant Professor of Anesthesiology and Pain Management and Neurological Surgery; Vikram Jakkamsetti, Ph.D., Instructor of Neurology; Michael Jessen, M.D., Professor and Chair of Cardiovascular and Thoracic Surgery; Bruce Mickey, M.D., Professor Emeritus of Neurological Surgery; Matthias Peltz, M.D., Professor of Cardiovascular and Thoracic Surgery and Surgical Director of Cardiac Transplant; Cameron Longfellow, Perfusionist; Debra Douglass, Chief Perfusionist; Levi Good, Ph.D., Visiting Senior Researcher in Neurology; Gauri Kathote, Data Scientist in Neurology; Gus Angulo, Research Technician in Neurology; Qian Ma, M.D., Ph.D., Senior Research Scientist in Neurology; Ronnie Brown, Senior Research Associate in Neurological Surgery; Misha Dunbar, DVM, Senior Staff Veterinarian; John Shelton, Lab Manager; and Sourav Patnaik, Senior Biomedical Engineering Specialist.
About UT Southwestern Medical Center
UT Southwestern, one of the nation’s premier academic medical centers, integrates pioneering biomedical research with exceptional clinical care and education. The institution’s faculty members have received six Nobel Prizes and include 26 members of the National Academy of Sciences, 20 members of the National Academy of Medicine, and 14 Howard Hughes Medical Institute Investigators. The full-time faculty of more than 3,100 is responsible for groundbreaking medical advances and is committed to translating science-driven research quickly to new clinical treatments. UT Southwestern physicians provide care in more than 80 specialties to more than 120,000 hospitalized patients, more than 360,000 emergency room cases, and oversee nearly 5 million outpatient visits a year. (TD/Newswise)